1. Field of the Invention
The present invention relates to an under-body frame of a vehicle including a floor of a vehicle, a mounting bracket on which a trailing arm of a rear suspension device is mounted, and various members for maintaining stiffness of the vehicle.
2. Description of Related Art
A lower part of a vehicle is structured such that various parts are installed on a panel called a floor. The floor comprises a front part and a rear part. Various parts are installed on a vehicle floor. The rear part of the floor is provided with rear wheel arches. The rear part of the floor is provided with side fires at both side ends thereof A rear suspension device is installed at a lower portion of the floor so as to be positioned near the rear wheel arch for maintaining driving stability. A representative of the An example of a rear suspension device is a Coupled Torsion Beam Axle (CTBA). In the CTBA, a torsion beam extending at a middle portion of the floor and trailing arms installed at both ends of the torsion beam serve as a frame. The trailing arm is provided with a coil spring and a shock absorber. The torsion beam prevents an axis of the vehicle from shaking using recovery force against torsion and is applied with lateral force, rear-to-front longitudinal force, and brake moment. The fixation of a portion to which the trailing arm is fixed and the lower part of the vehicle around the fixed portion must be sufficiently secured in order to draw the maximum performance out of the suspension device.
However, the known suspension device is designed focusing on the layout of a lower part of the vehicle and the inside space of the vehicle rather than considering mounting fixation security. For such a reason, the suspension device cannot sufficiently perform its intrinsic function, and durability of the suspension device decreases as time passes. Further, it is needed to change the mounting structure of the known suspension device to increase steering stability and comfortableness of riding in the vehicle.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.